On Thu, Oct 12, 2023 at 10:45:07AM +0530, Anup Patel wrote: > We extend the existing RISC-V SBI earlycon support to use the new > RISC-V SBI debug console extension. > > Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx> > --- > drivers/tty/serial/Kconfig | 2 +- > drivers/tty/serial/earlycon-riscv-sbi.c | 32 +++++++++++++++++++++---- > 2 files changed, 29 insertions(+), 5 deletions(-) > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > index bdc568a4ab66..cec46091a716 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -87,7 +87,7 @@ config SERIAL_EARLYCON_SEMIHOST > > config SERIAL_EARLYCON_RISCV_SBI > bool "Early console using RISC-V SBI" > - depends on RISCV_SBI_V01 > + depends on RISCV_SBI > select SERIAL_CORE > select SERIAL_CORE_CONSOLE > select SERIAL_EARLYCON > diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c > index 27afb0b74ea7..c21cdef254e7 100644 > --- a/drivers/tty/serial/earlycon-riscv-sbi.c > +++ b/drivers/tty/serial/earlycon-riscv-sbi.c > @@ -15,17 +15,41 @@ static void sbi_putc(struct uart_port *port, unsigned char c) > sbi_console_putchar(c); > } > > -static void sbi_console_write(struct console *con, > - const char *s, unsigned n) > +static void sbi_0_1_console_write(struct console *con, > + const char *s, unsigned int n) > { > struct earlycon_device *dev = con->data; > uart_console_write(&dev->port, s, n, sbi_putc); > } > > +static void sbi_dbcn_console_write(struct console *con, > + const char *s, unsigned int n) > +{ > + phys_addr_t pa = __pa(s); > + > + if (IS_ENABLED(CONFIG_32BIT)) > + sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE, > + n, lower_32_bits(pa), upper_32_bits(pa), 0, 0, 0); > + else > + sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE, > + n, pa, 0, 0, 0, 0); > +} > + > static int __init early_sbi_setup(struct earlycon_device *device, > const char *opt) > { > - device->con->write = sbi_console_write; > - return 0; > + int ret = 0; > + > + if ((sbi_spec_version >= sbi_mk_version(2, 0)) && > + (sbi_probe_extension(SBI_EXT_DBCN) > 0)) { > + device->con->write = sbi_dbcn_console_write; > + } else { > + if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) > + device->con->write = sbi_0_1_console_write; > + else > + ret = -ENODEV; > + } > + > + return ret; > } > EARLYCON_DECLARE(sbi, early_sbi_setup); > -- > 2.34.1 > Reviewed-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>